Cylinder machine for forming a web in paper making



March 14, 1961 s u o w T 2,974,726

CYLINDER MACHINE FOR FORMING A WEB IN PAPER MAKING Filed April 15, 1958 screen. -flowed into the vat circle space is the same as the pecrease. of loss of production and a speed limitation since a tendexpensive, and occupies a much larger floor that of the cylinder machine.

United States PatentO RisakuJOkaWa and Riichiro Okawa, both of 939 Z ushi, Zushi-shi, Kanagaw'a-ken, Japan Filed Apr. 15, 1958, Ser. No. 728,599

2 Claims. (Cl. 162-328) This invention relates to a cylinder paper machine particularly to a machine of the type in which an endless belt travels in the same direction as that of the cylinder mold at an approximately same rate of the molds peripheral speed maintaining a substantially vat circle space between the belt and mold wherein an aqueous suspension of paper pulp stock is flowed at a comparatively rapid rate by controlling the velocity of the flow of paper pulp stock so that its speed is approximately equal to the peripheral speed of the rotating cylinder mold, so that a uniform dimensionally stabilized paper web may be formed and the cardinal directions, i.e. machine direction and cross direction are almost equal in the paper grain. I

According to the ordinary and conventional type of cylinder machine, paper web is formed in such a way that the stock is usually introduced into the vat circle space provided between the cylinder mold and a semicircular vat wall and the water is made to pass through the face of the cylinder mold under a static head and then discharged out at its ends, leaving the pulp fibers as a sheet on the face of the cylinder mold wire mesh And even if the initial velocity of the stock ripheral speed of the rotating cylinder mold the velocity -is reduced gradually by the frictional drag caused against the vat circle wall surface, and the pulp fibers tend to align themselves in the same direction as the direction of rotation of the rotating mold, i.e. in the machinedirection. Particularly, if the cylinder molds peripheral speed increases, the tendency toward alignment will in- Therefore, the machine has the disadvantage ency develops to serve a somewhat limited kind of pro duction purpose.

n the contrary, in the ordinary and conventional type of Fourdrinier machine, as the stock flows onto the endless traveling wire screen supported on the table rolls, the uniform layer of fibers is filtered out by means of suction boxes and of contact of the table rolls to the wire screen and then transformed into paper web while the pulp fiber layer is still suspended in water more or less being moved forward at the same speed andthe same direction of the traveling wire screen on which the web itself is laid thereon. Therefore, this type of machine has such characteristics that the paper produced will not have the cardinal directional strengths, i.e. machine di-- -frequently by friction against'the suction boxes and table rolls. Moreover, the structure is long, complicated and space than A primary object of this invention is to provide a ma ing mold.

t r, 2,974,726 Patented Mar. 14', 1951 chine of the type in which the formation of paper web is uniform, dimensionally stabilized and the fibers are uniformly interwoven and interlocked both lengthwise and crosswise to the paper grain, and also the production speed of the machine is increased higher than that of the conventional type of the cylinder machine whic has commonly been under operation.

Another aim of the invention is to reduce the wear and tear of the wire screen,'and modification and improvement on the cylinder type paper machines in common use presently.

In accordance with our invention, therefore, in place of the stationary fixed semi-circular vat circle wall which is purposely provided to form a vat circle square between the wall and mold surface of the ordinary and conventional type of cylinder machine, we propose to have an endless belt travel alongside the mold periphery leaving only the upper part of the mold uncovered, maintaining a certain arcuate space next to the mold outer surface. The belt travels at the same peripheral speed as that of the mold and it travels in the same direction as that of rotation of the mold. The paper stock flows into the vat circle and is filtered out by the static head and the fiber is deposited on the outer surface of the wire mesh covering the mold and forming the paper web. The water in the stock which travels along the circle space is reduced due to drainage through the wire mesh; thus by making the initial velocity of the stock flowing into the space a little faster than the peripheral speed of the mold, the fibers are not only aligned to the machine direction, but also to the cross direction not completely but approximately at the same rate to bring about the result of two approximately equal cardinal directional strengths of the paper.

In the cylinder machine of the ordinary and conventional type, the fibers which have already been aligned to the cross direction as well as to the machine direction at the beginning are pulled backwards and forced to align themselves in the machine direction due to the natural result of the velocity of the stock at the overflow end of the stationary fixed vat circle wall which is reduced more slowly than the peripheral speed of the rotat- In this invention, however, the pulp stock around the feeding end of the vat circle wall, the structure of which is formed by an impervious endless belt, isrsuspended and is'almost in a quiescent state since the .moving wire of the mold surface as the stock moves towards the same direction of the mold rotation and at almost the same speed as the peripheral speed of the moving mold surface under aid of the endless traveling belt, effecting it as if the function of the Fourdrinier machine wire participated. This mechanical function is comparable with that of the web formation in the Fourdrinier machine in which the stockis flowed onto a rapidly traveling endless flat wire screen and moves with it at the same speed as that of the traveling wire without any centrifugal effect, as in the ordinary and conventional cylinder machine, making the stock on the wire consequently in the complete quiescent state and 'the water is removed by the table rolls and suction boxes while the pulp fiber sheet is laid in a quiescent manner on the traveling wire screen during travel thereof.

In the paper produced by this newly invented cylinder mold machine the fibers therein are not aligned primarily in the machine direction as it appears in the paper made by the ordinary and conventional type of the cylinder machine but has approximately the same strength in two cardinal directions, i.e., machine direction and cross direction, and uniform dimensional stabilities. This is due to the fact that the traveling endless belt which moves along the mold outer surface at approximately the same speed as the peripheral speed of the moving cylinder mold has direction, i.e. the direction of rotation of the mold. Since there is no predominance in the orientation of the fibers along the machine direction, the peripheral speed of the mold may be raised and thus the production speed of the machine is greatly increased. Furthermore, in the'Fourdrinier machine, the wear and tear of the wire screen that is caused by the friction against the table rolls and suction boxes is frequent and heavy, but the wire screen on the cylinder mold, according to the fundamentals of the cylinder machine does not wear out as frequently as the Fourdrinier machine, since there is nothing to be touched with the wire to cause frictional wear. Moreover, another feature of this invention is to provide an effective and efiicient functional results in paper making that cannot be achieved with the Fourdrinier or the Cylinder machine of the conventional type. The present invention adopts the best features of both the conventional types of machines, the Fourdrinier and Cylinder machine and eliminates the undesirable features thereof by new and improved structure.

Said objects and other objects of the present invention have been attained by an apparatus which comprises a cylinder paper machine comprising an impervious endless traveling belt which is maintained at a certain clearance to the mold peripheral surface beneath the cylinder mold and travels in the same direction as the direction of rotation of the rotating mold at approximately the same speed as the peripheral speed of the rotating cylinder mold. The upper side of the mold is exposed to a traveling endless felt belt which strips the paper web from the pervious mesh screen Wire cover on the mold surface not encircled by the impervious belt.

The novel features which are believed to be characteristics of the present invention are set forth with particularity in the appended claims. The present invention itself, however, both as to its construction and operation, together with further objects and advantages thereof, may best be understood by references to the following description taken in connection with the accompanying drawings, in which the same members are indicated by the same references, and in which:

Fig. l is a diagrammatic sectional end elevation view of a paper making machine embodying the principles of this invention;

Fig. 2 is a plan view of the machine in Fig. 1; and

Fig. 3 is an enlarged view of a portion taken on A of Fig. 2 as viewed in the direction of the arrow.

Referring to Fig. 1, illustrating a paper making machine according to the invention in which is shown a vat 1 having a rotatably driven cylinder mold 2 which is covered peripherally with wire mesh 3 shown fragmentarily in Fig. l and Fig. 2. The shaft 3 is mounted on side walls 4, 5 of the vat for rotation disposed so that the mold rotates in the vat partially submerged in a manner later described in the same manner as in the ordinary type of cylinder machine. As shown in Fig. 3, a pair of revolving rings '7, only one of which is shown, are coupled at either end of the mold, each confronting a respective ring 8 fixed stationary on the inner surface of the vat wall 5 and projecting inwardly as shown. A packing ring 10 is fixed to the ring 8 allowing the revolving ring 7 to rub against it tightly forming a fluid-tight seal so as not to allow any water leakage through the seal while the mold rotates in the vat 1.

Pulp stock to be formed into a paper web by the mold is fed into the vat l through a wide supply inlet 12 and the level of the aqueous suspension of paper pulp stock is maintained in operation at a level 14 so that the mold 2 is partially submerged as shown. The paper pulp stock is flowed into an arcuate space, later described, under a static head controlled by having the level of the water internally of the moldat a lower level 15 so that the paper web is formed on the wire mesh 3 by flowing, the stock into said arcuate space.

According to our invention, a pair of flanges 16, 18 having a diameter which is little larger than that of the mold 2 are fixed on opposite-ends of the cylinder mold for rotation therewith. An arcuate space is formed inbetween the wire mesh 3 and an endless belt 21 made, for example, of rubber or other suitable synthetic fiber materials. The belt 21 has an upper runsupported in position beneath the mold by a pair of rotatable guide rolls 23, 24 which hold the belt upper run frictionally engaging the peripheral surfaces of the flanges and spinning the flanges forming the arcuate space 19 which is shaped substantially as a half-cylinder. A second pair of rotatable guide rolls 26, 28 cooperate with the first-mentioned guide rolls to hold the belt in position. The belt 21 is preferably reinforced transversely, as for example, with internal transverse rods 30 so that it is in constant frictional engagement with the peripheral flanges.

The mold is variably driven by means, not shown, so that the belt 21, travels in a direction of rotation of the wire mesh on the mold and at approximately the same speed as the peripheral speed of the rotating mold. Thus in operation there is no frictional drag on the fibers, being laid on the wire mesh, due to the belt surface as in the ordinary and conventionally built stationary fixed vat circle wall. A paper web of fine formation, in which the pulp fibers are well and harmoniously interlocked and interwoven, can be produced by suitably adjusting the initial velocity of the stock flowing into the space 19 to a little higher velocity than the peripheral speed of the mold depending on the kind, thickness, freedom of the stock, production speed and web thickness. In the example shown the direction of rotation of the mold is clockwise so that the stock flows into the space 19 on an end thereof adjacent the roll 24. The excess stock flowing out of the other end of the space 19 may be guided back under the endless traveling belt 21 by an agitator 33 and re-fed into the space 19 with an added new stock continuously flowing in through inlet 12. Furthermore, the excess stock out of the overflow end of space 19 may be returned to the original feeding place by means of a circulation pump (not shown in the drawing) and fed in with newly supplied stock through a flow box and nozzle (both now shown in the drawing) into the vat circle space from the space 19 with a certain pressure, this will increase greatly the production speed of the machine; and in the formation of the paper, there is less tendency of the fibers toward alignment to the machine direction may be secured by suitably increasing the initial velocity of the stock to be pressure-flowed into the space 19 at a velocity a little higher than the mold peripheral speed depending upon the kind, thickness and freedom of the stock. In order to maintain the level of the water in the mold lower than the level of the aqueous suspension of pulp stock in the vat 1 the vat is provided with a small chamber 35 in communication with the interior of the mold through apertures, not shown, provided in the wall 5 of the vat and the corresponding end of the mold. A gate is formed of two upstanding partitions 36, 37. The gate partition 37 moves vertically upwardly and downwardly relative to the gate partition 36 which forms the lower part of the gate. Movement of the partition 37 is accomplished by rotation of an elongated threaded member 39 which allows positioning the gate partition 37 at a desired height for control of the, water level 15. Any overflow flows into a well 40 and the water'is pumped out of the well by a pump 41 which takes a suction on the well through a conduit 42 and discharges the water through a conduit 43.

The pump 41 is driven off of the agitator 33 by means of a belt.44. The agitator is rotatably driven by means not shown which also drive the mold. The web is formed by adherence of the fibers to the screen 3 and is stripped off the mold wire 3 by an endless traveling felt belt 45 guided over a coach roll 46 which is biased by a weight 47 into engagement with the periphery of the mold. The roll 46 is,mounted for angular movement and rotation on a pivoted member or arm 49 on which the weights act.

While we have described particular embodiments of our invention, it will, of course, be understood that we do not wish our invention to be limited thereto, since many modifications may be made and we, therefore, contemplate by the appended claims to cover all such modifications as fall within the true spirit and scope of our invention.

We claim:

1. A cylinder mold paper making machine comprising, a rotatably driven hollow cylinder mold having a pervious, fine mesh wire screen surface arranged for the formation thereon of a paper web deposited from an aqueous suspension of paper pulp stock, means for removing Water from the mold interior, said mold having radial flanges at opposite ends thereof of equal diameter, an endless, impervious traveling belt having a run disposed for traveling beneath the mold against the peripheral surfaces of said flanges defining an arcuate space between the belt and the screen shaped substantially as a half-cylinder, rotatable guide means holding said run in position beneath the mold frictionally engaging said peripheral surfaces of the flanges and spanning the flanges defining said arcuate space thereby to cause the impervious traveling belt to travel with the driven mold in a common direction at a speed substantially equal to the peripheral speed of the mold, means for moving an aqueous suspension of paper pulp stock into said space in the direction of rotation of the mold, 3

and means for removing the paper web formed on the periphery of the screen from the mold outside of said space.

2. A cylinder mold paper making machine comprising, a rotatably driven hollow cylinder mold having a pervious, fine mesh wire screen surface arranged for the formation thereon of a paper web deposited from an aqueous suspension of paper pulp stock, means for removing water from the mold interior, said mold having radial flanges at opposite ends thereof of equal diameter, an endless, impervious traveling belt having a run disposed for traveling beneath the mold substantially against the peripheral surfaces of said flanges defining an arcuate space between the belt and the screen shaped substantially as a half-cylinder, rotatable guide means holding said run in position beneath the mold frictionally engaging said peripheral surfaces of the flanges and spanning the flanges defining said arcuate space thereby to cause the impervious traveling belt to travel with the driven mold in a common direction at a speed substantially equal to the peripheral speed of the mold, means for moving the aqueous suspension of paper pulp stock into said space in the direction of rotation of the mold at a speed of entry commensurate with speed of rotation of the mold, and means for removing the paper web formed on the periphery of the screen from the mold outside of said space.

References Cited in the file of this patent UNITED STATES PATENTS 0 1,831,018 Little Nov. 10, 1931 2,473,269 Adams June 14, 1949 2,473,270 Adams June 14, 1949 

